SQL Monitor outputs the information that it collects from the SQL Server instance and the Host Machine that it is monitoring. Without further information I cannot say why this might be outputting this hexadecimal string only that this would be what the monitored entity is returning.

If you can send me the SQL Monitor error logs, confirm which alert type is giving this and anything else that you think might be useful. Then please send an email to support@red-gate.com and quote F0069135 in the subject line.